Which choice shows a relationship that is DIFFERENT from the other three choices?

A.

There are [tex]$3$[/tex] bacteria in a petri dish, and the number of bacteria doubles every hour.
[tex]$
b(x)=2 \cdot 3^x
$[/tex]

\begin{tabular}{|c|c|}
\hline[tex]$x$[/tex] & [tex]$b(x)$[/tex] \\
\hline 0 & 3 \\
\hline 1 & 6 \\
\hline 2 & 12 \\
\hline
\end{tabular}

B.

A car travels at a constant speed of 60 miles per hour.
[tex]$
d(t) = 60t
$[/tex]

\begin{tabular}{|c|c|}
\hline[tex]$t$[/tex] & [tex]$d(t)$[/tex] \\
\hline 1 & 60 \\
\hline 2 & 120 \\
\hline 3 & 180 \\
\hline
\end{tabular}

C.

The area of a square increases as the square of its side length.
[tex]$
A(s) = s^2
$[/tex]

\begin{tabular}{|c|c|}
\hline[tex]$s$[/tex] & [tex]$A(s)$[/tex] \\
\hline 1 & 1 \\
\hline 2 & 4 \\
\hline 3 & 9 \\
\hline
\end{tabular}

D.

The value of an investment increases according to the formula for compound interest.
[tex]$
V(t) = P(1 + r)^t
$[/tex]

\begin{tabular}{|c|c|}
\hline[tex]$t$[/tex] & [tex]$V(t)$[/tex] \\
\hline 1 & [tex]$P(1 + r)$[/tex] \\
\hline 2 & [tex]$P(1 + r)^2$[/tex] \\
\hline 3 & [tex]$P(1 + r)^3$[/tex] \\
\hline
\end{tabular}



Answer :

To find which choice shows a relationship that is different from the other three choices, we need to compare the values in the table with the expression for [tex]\( b(x) = 2 \cdot 3^x \)[/tex].

Given the function:
[tex]\[ b(x) = 2 \cdot 3^x \][/tex]

Let's calculate the number of bacteria at each time point [tex]\( x \)[/tex] to see if the provided table matches this function:

1. For [tex]\( x = 0 \)[/tex]:
[tex]\[ b(0) = 2 \cdot 3^0 = 2 \cdot 1 = 2 \][/tex]

2. For [tex]\( x = 1 \)[/tex]:
[tex]\[ b(1) = 2 \cdot 3^1 = 2 \cdot 3 = 6 \][/tex]

3. For [tex]\( x = 2 \)[/tex]:
[tex]\[ b(2) = 2 \cdot 3^2 = 2 \cdot 9 = 18 \][/tex]

So, the calculated values are:
[tex]\[ \begin{array}{|c|c|} \hline x & b(x) \\ \hline 0 & 2 \\ \hline 1 & 6 \\ \hline 2 & 18 \\ \hline \end{array} \][/tex]

Now, let's compare these values with the given table:

[tex]\[ \begin{array}{|c|c|} \hline x & b(x) \\ \hline 0 & 3 \\ \hline 1 & 6 \\ \hline 2 & 12 \\ \hline \end{array} \][/tex]

It is clear that the given table does not match our calculated values for [tex]\( x = 0 \)[/tex] and [tex]\( x = 2 \)[/tex]. The correct values should be:

- At [tex]\( x = 0 \)[/tex], the value should be 2, but the given table shows 3.
- At [tex]\( x = 2 \)[/tex], the value should be 18, but the given table shows 12.

Therefore, the relationship shown by the given table is different from the correct exponential relationship described by the formula [tex]\( b(x) = 2 \cdot 3^x \)[/tex].